IntelliJ IDEA 2018.1 Help

Keymap:

Merge Tags

The Merge Tag intention allows you to merge two sequential and compatible XML tags into one larger tag. The tags to merge must have the same name and attributes. To merge two tags, simply select the first tag to merge, and invoke the intention with Alt+Enter. Then select Merge Tags, and the tags will be merged. Merging effectively replaces the two tags with a new tag. The new tag will have the same attributes as the original tags, and its contents will be created by appending the contents of the first tag with the contents of the second.